Adjustable chair.



Nq. 718,372; PATENTBD JAN. 13,' 1903. T. M. MUKEB.

ADJUSTABLE CHAIR.

APPLICATION FILED MAY 31, 1902.

No nonni..

/N/NTOR.-

ATTORNEY.

UNITED STATES PATENT (')FFici-i.

THOMAS M. MCKEE, OF GREENFIELD, INDIANA.

ADJUSTABLE CHAIR.

SPECIFICATION forming part of Letters Patent N o. 718,372, dated January 13, 1903. Y

i Application led May 31, 1902. Serial No. 109.617. (No model.)

.T0 a/ZZ whom, t may concern.-

Be it known that I, THOMAS M. MCKEE, a citizen of the United States,residing at Greenfield, in the county of Hancock and State of Indiana, have invented n-ew'and useful Improvements in Adjustable Chairs; and I do declare the following to be a full, clear, and exact description of the invention, reference being had to the accompanyingdrawings, and to the letters of reference marked'thereon, which form a part of this specification.

My invention relates to knockd'ow-n adjustable chairs in which the back may be adjusted to various angles and the seat also elevated and depressed without requiring horizontal movements thereof.

My objects Iare to provide an inexpensive chair in which the seat may be moved only in vertical directions in harmony with the movements of the chair-back, to provide frictional devices cheaply that will prevent too free and annoying movements of the back and the seat while in use when it may not be desired to Change the adjustment, but which will permit free automatic intentional adjustment by the person occupying the chair, and to also provide a back-frame that may be readily packed for shipment without occupying unnecessary space.

The invention consists in a main frame having novel features of construction, a vertically movable and guided seat-frame,a back-frame, a pair of rocking arms pivoted in the main frame and employed for supporting-the backframe and also for partially supporting` the seat-frame and for operating the same, and sliding friction-wedges connected to the rocking arms and directly supporting the seatframe; and the invention consists also in the novel parts and in the combination and arrangement of parts, as hereinafter particularly described and claimed.

Referring to the drawings, Figure l represents a front elevation View of a chair embodying my improvements without cushions; Fig. 2, a longitudinal Vertical sectional view in which the parts are adjustedY for sitting position; Fig. 3, a horizontal sectional view taken above the seat-frame and showing a fragmentary top plan thereof and also the plan of the main frame; Fig. 4, a longitudinal vertical sectional view showing the parts adjusted for reclining position Fig. 5, an enlarged detail view of a rocking arm and connected parts; Fig. 6, Yan inside View of a rear`r frame-post; Fig. 7, a rear plan view of a rocking arm; Fig. 8, a sectional View of part of the rocking arm; Fig. 9, a perspective viewof ai friction-wedge, and Fig. 10 a transversesectional View of a rocking arm and part ofthe .16o

back-frame attached thereto.

In the drawings similar reference-characters indicate similar parts throughout.

In practicalljT carrying out myinvention I provide a suitable main frame, which essentially comprises four upright posts A A' B B' and provide the legs and the supports forthe arm-rests, longitudinal -side rails .C C', attached to the front and rear posts, and transverse front and rear rails D and D', respectively, which connect the two sides together by attachment to the posts. The arm-rests E E are secured upon the tops of the posts. Braces F F are attached at the front posts to the inner sides of the side rails and to the front rail at or near the lower portions thereof. Each rear post B B' has a socket journalbearing d at the inner side thereof in alineinent with each other a short distance above the rear rail D.

rI`hel rocking arms G G' are composed of suitable metal,and each one is provided,some what near one end thereof, with a trunnion b, projectingfrom the rear side thereof into the bearing a., so that the arms are pivotally connected to the rear posts. A balance-spring His usuallyvwound around each trunnion and attached at one end to the arm andat the other end thereof to the post, which may be suitably accomplished by bending the ends of the spring and inserting them into holes d and e in those parts. The springs are so strained that they tend to hold the arms toward vertical positions. In some cases the balance-springs may be situated elsewhere, however, and be suitably formed. Flanges fproject from the front face of each arm.

Near the trunnion in each arm is a threaded hole g, in which is a screw-bolt I, having a thumb-screw head h and situated between a pair of the flanges f. In Fig. 4, indicates theapproxirnate location of the trunnions.

IOO

The end of each rocking arm opposite to the flanged end is preferably bifureatcd and provided with a permanent bearing-pin j.

The friction-wedges J preferably have holes 7c, in which are secured spreaders Z, connecting the two wedges that are employed together. The wedges are situated at the inner sides of the side rails, and they have each an inclined bearing-face m at the under side of the forward end, engaging the upper edge of a brace F or F, upon which the wedges may slide. The opposite end of each wedge has a notch n, at the bottom of which is a bearing resting upon one of the pins j, and thus the wedges are supported by the pins and the braces.

The seat-frame comprises sides K K and. ends L L', all secured together, the side rails resting upon the Wedges J and preferably having small projections g at the rear portions thereof. Suitable guides for the seat-frame may comprise projecting studs or ribs e, attached to the side rails C C and extending into groovesp in the seat-frame sides, or other suitable forms of guides may be employed.

The back-frame comprises side rails M M and connecting end rails N N and suitable slats. The lower ends of the rails are fitted to the arms G G between the fiangesfand are secured by means of the bolts I, extending through suitable holes therein. Usually end stops r are provided for the back-frame for supporting the same independently of the bolts I, which may in some cases be omitted and mere retaining pins or catches substituted therefor.

Any suitable forms or types of cushions may be employed, and the seat-frame may be adapted for receiving either soft or spring cushions.

In assembling the parts it is only necessary to set the rocking arms in their places, hang the wedges on the arms, and drop the ends having the inclined bearing-faces upon the corner-braces, place the seat-frame upon the wedges, and then insert the back-frame rails into the socket-like ends of the rocking arms and secure them. In crating for shiplnent the back-frame will be short enough to conveniently lie upon the seat.

In practical use when the back is nearly vertical the wedges will be drawn rearward, permitting the seat to assume its lower level, and by pushing backward against the chairback the wedges will be forced forward, and thus force up the seat-frame. In all positions the frictional resistance of the wedges will be sufficient to hold the back and the Seat steady against oscillatory short movements.

Having thus described my invention, what I claim as new is- 1. An adjustable chair comprising a main frame, rocking arms mounted in the main frame, friction-wedges having the rear ends thereof pivotally supported by the rocking arms, supports upon which the forward portions of the wedges are slidingly mounted, a vertically-movable seat-frame mounted upon the wedges,means for retaining the seat-frame against horizontal movements, and a backframe mounted on the rocking arms.

2. An adjustable chair comprising a main frame, rocking arms having anges at their upper ends and pivoted in the main frame, friction-wedges having the rear ends thereof pivotally supported by the rocking arms, supports upon which the forward portions of the wedges are mounted, a verticallymovable seat-frame mounted upon the wedges, guides for the seat-frame, and a back-frame mounted on the rocking arms and engaged by the flanges thereof.

3. An adjustable chair comprising a main frame, rocking arms having bearing-pins at the lower ends thereof and mounted in the main frame, wedges having bearings at their rear ends engaging the bearing-pins whereby the rear ends of the wedges are pivotally supported, bearings attached to the main frame whereby the forward portions of the wedges are supported, a movable seat-frame mount-- ed upon the wedges, guides restraining the seat-frame against horizontal movements, and a back attached to the rocking arms.

In testimony whereof I afx my signature in presence of two witnesses.

THOMAS M. MCKEE.

Witnesses:

WM. I-I. PAYNE, E. T. SILvIUs. 

